Cravings for chips: Why the whole bag is always eaten empty
Chips really are not part of a healthy diet. If you consume too much of it, you not only risk getting fat, but also often get pimples, blackheads and blemished skin. Although most people are aware of this, it is usually difficult to stop once the bag has been opened. But why is that? German researchers have now dealt with this question.
After the "crime scene" the chip bag is mostly empty
Everyone actually knows that you shouldn't eat too many chips, as they are known as fattening foods. But especially at a cozy TV evening, if you watch a “crime scene” or a blockbuster together, many can no longer stop nibbling. Only when the bag is empty is the end. But why is that actually the case? German scientists have now dealt with this question again.
Snacks with an addictive factor
"Hedonic hyperphagia" - that's what scientists call it when you can't stop eating potato chips or chocolate.
This so-called “potato chip effect” has already been shown in scientific studies in the past.
A few years ago, researchers at the Friedrich Alexander University Erlangen-Nuremberg (FAU) reported experiments with rats that showed why chips are addictive.
At the time, the scientists wrote in a communication that "the ratio of how a food is composed plays an important role": "50 percent carbohydrates and 35 percent fat tempt you to snack", according to the experts.
However, the craving for chips could only be partly explained by the fat and carbohydrate content.
Rats, which received the same fat-carbohydrate mixture as is present in potato chips, showed less pronounced activation in the brain than animals after eating the chips.
Brain reward center is activated
The Erlangen researchers have now carried out a follow-up study with humans and came to the conclusion that the higher the Body Mass Index (BMI), the more activated the reward center in the brain is when eating chips, reports the news agency dpa.
As part of their study, the researchers first gave almost 20 men and women potato chips and three days later zucchini. Before and after, her brain was examined in nuclear spin.
According to the information, the brain reacted particularly strongly to the consumption of the chips, similar to what had previously been observed in rats.
"For us, the most interesting result was that depending on the person's BMI, exactly the same brain structure as in rats changes - the nucleus accumbens," says study leader Andreas Hess, according to dpa.
It is a region that participates in the so-called reward center of the brain. However, the experts do not yet know why. "We are researching this further, we are at a very critical point here."
The reward system reacts somewhat differently in obese people
The effect of eating on the brain is sometimes compared to that of drugs. Dopamine plays a major role in this.
According to researchers, this can create a kind of vicious cycle, which means that you need more and more of a certain substance to get the same euphoric state, the same sense of reward - so you become addicted to it.
However, according to Isa Mack from the University Hospital Tübingen, the subject of eating addiction is discussed very controversially in science. Nutrition and the reward system always belonged together.
"For everything that is important for self-preservation and self-propagation, the reward system must start," said the expert, according to dpa.
It is an "evolutionary legacy" that it reacts to "sweet and fatty". In addition, it is known that when eating, the reward system reacts somewhat differently in very overweight people.
"But that doesn't mean that it was always like that or can't be changed," says Mack. "Brain activities are changeable," said the nutritionist. For example, they changed after losing weight.
Researchers were surprised by the result
Humans may also be interested in the results of the previous rat study, which showed that potato chips "lead to activation in the reward center," as Hess explained.
At that time, the researchers had actually expected that the fattening the fodder - the higher the energy content, the more attractive the food would be. "But that was not the case," explained Hess. "The rats clearly prefer the ratio of about 35 percent fat to 45 percent carbohydrates."
In addition to chips, this ratio is shared by many other foods such as chocolate or nut nougat cream.
“The mammalian brain is not only interested in high energy content, but in this mixture ratio. This speaks particularly well to the reward center, ”explains the researchers from Erlangen.
The evidence for this is still pending, but this should not be much different in humans either.
Since humans as a species are still very young and good nutrition, as we have it today, the human brain is still trying to eat as much "good", ie rich, food as it is available.
"This mixture may be physiologically ideal for the body - it provides quickly mobilizable energy through the carbohydrates and storable energy in the fat portion", so the hypothesis of Hess.
Do not take the whole pack with you in front of the television
"It is surprising that rat and human seem to behave relatively similarly here," said nutritionist Hans Hauner from the Technical University of Munich in the dpa report.
This principle used to be very useful because food was not guaranteed. "We have only had an excess of food energy for 50 years, so this principle is increasingly becoming a problem and in particular promotes obesity," said the expert.
However, according to Isa Mack, other things also played a role in the popularity of a food.
As stated in the agency announcement, the Erlangen researchers had ruled out in their study that salt plays a major role in the attractiveness of the feed, i.e. the chips. Mack doesn't think that is irrelevant.
"If we had chips without salt and without seasoning, we would not eat them in large quantities," said the expert.
In addition, fat alone makes eating or feeding more attractive simply by its amount of energy. However, at a certain point, the body can no longer handle too much fat and it will no longer taste good.
"If I had half a butter, I would feel sick," said Mack, who pointed out that the food industry had also extensively tested which mixing ratio of the chip components was most popular with humans.
Andreas Hess therefore has advice on how to better control cravings for chips:
"Go consciously: Don't take the whole bag in front of the television, just a small bowl." This tricking yourself should help that not every pack is emptied on the sofa. (ad)